Telephone calling dial device



Jan. 5, 1943. G. R. LUM 2,307,463

TELEPHONE CALLING DIAL DEVJTICE Filed Feb. 6, 1942 4 FIG. i

' 2 sheets-$1199 1 WQWQ ATTORNEY,

G. R. LUM TELEPHdNE CALLING DIAL DEVICE Jan. 5, 1943.

Filed Feb. 6, 1942 2 sheet ssheet 2 FIG. 3

BIC j A T7'ORNEV Patented Jan. 5, 1943 TELEPHONE CALLING DIAL DEVICE George R.

Lum, New York, N. Y., assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., acorporation of New York Application February 6, 1942, Serial No. 429,727 Claims. (01. 179-80) This invention relates to telephone calling dial devices and more particularly to telephone calling dial devices inwhich a finger wheel is supported on the rotatable shaft of the. device.

An object of the invention is to provide an improved structure and arrangement for flexibly supporting the finger wheel and which permits ready application of the finger wheel to the device and removal therefrom.

A feature of the invention resides in a spider type flexible support for the finger wheel.

Another feature resides in the structure of the finger wheel.

In the drawings,

Fig. 1 is a side elevational view, partly in section, of the calling dial device embodying the invention.

Fig. 2 shows, in exploded arrangement, the dial device and the finger wheel.

Fig. 3 corresponds to Fig. 1 but shows a modification of the finger wheel.

Fig. 4 is a top plan view, partly in section, of the finger wheel and the flexible support therefor, and is drawn in reduced scale relative to Figs. 1, 2 and 3.

Fig. 5 is a view in perspective of a fragmentary portion of the finger wheel and is somewhat enlarged relative to Fig. 4.

Fig. 6 corresponds to Fig. 5 but shows in addition a fragmentary portion of the flexible support; and,

Fig. 7 is a sectional view of the parts shown in Fig. 6 and taken on the line 'l-! in Fig. 4.

It has been common practice to make finger wheels, for telephone calling dial devices, of metal and to directly mount the finger wheel on the rotatable shaft of the device, the finger wheel being held in place by means of a nut, screw threaded on the shaft.

It is also common practice to provide an apertured hub portion on the finger wheel and to mount in the hub portion a card and a transparent cover for the card, the card having the telephone substation name and number thereon and the card and the transparent cover being removable through the top of the hub portion to permit access to the nut on the rotatable shaft.

The trend is now, however, to make the finger wheel of some molded plastic material. In some cases it is desirable to make the finger wheel of transparent molded plastic material to enhance the appearance of the device and in order that light may pass through the finger wheel to letter and number characters on the calling device.

Finger wheels of moldedplastic material are not as strong as the metal finger wheels and it is found advantageous to provide a fiexiblesupport for the finger wheel instead of mounting the finger wheel directly on the rotatable shaftof the .calling device.

In this invention, the flexible spider type support for the finger wheel is mounted on the rotatable shaft of the device and the finger wheel is mounted on the spider type support, the finger wheel being formed to receive outer end portions of the spider type support. Means are provided in the finger wheel and the support to latch the wheel in required position on the support. The finger wheel may be readily applied to or removed from the spider type support without requiring any access through the top of the finger wheel. The finger wheel is arranged so that the station number card is inserted only from the underside or the finger wheel and the hub portion of the wheel may have an integral window in place of the transparent cover for the card.

The telephone calling dial device as shown in Fig. 1 comprises a casing HI, and a finger wheel II, the finger wheel H being supported above the casing ill. The finger wheel 5! is supported by the flexible spider type support 52, the structure of which will be subsequently described. The support I2 is supported on a rotatable operating shaft it of the device and is held in posi- ,tion. on the shaft l3 by means of a nut 14. The shaft it extends downward through the casing Ill and may be manually operated by means of the finger wheel H to wind up a spring (not shown) but which, as well-known in the art, is ,part of a spring motor which serves .to return the finger wheel to normal position and as a driving means for a contact controlling device l5 which operates spring contacts is and IT to control the sending of signal pulses over a line system to obtain a desired call connection. A ringshaped dial it bearing groups of letters and numerals on its upper face is supported in the top of the casing iii, the groups being arranged in positions to be separately observed through the finger holes 28 provided in the finger wheel 'I I, all of which is well understood in the art. The finger wheel H is made of material suitable for molding to required form in a die and may be made for instance of a synthetic resin. The sfinger wheel ii in Figs. 1 and 2 is provided with the usual finger holes 2b to facilitate manualrotation of the finger wheel in dialing; a telephone call. The central portion of the finger wheel l l is hollowed outfromithe under surfacelto, pro ;vide a circular indentation 2i and toyleaveacigoss the top of the central portion a window 22 which is an integral part of the finger wheel. The indentation 2| is defined by the'circular side wall 23 and the under surface of the window 22. The side wall 23 of the indentation 2| is recessed at spaced points to provide the recesses 24, 25 and 2 6 to receive respectively the outer end portions of the arms 27, 28 and 29 of the spider type support I2. The recesses 24, 2'5 and 26 are open at the bottom and closed at the top so that when the finger wheel II is suitably placed on the spider type support I2, the arms 27, 28 and 29 will pass upwardly in the respective recesses 24, 25 and 26. The width of the outer end portion of each arm of the spider type support I2 is slightly less than half the length of its receiving recess in the finger wheel II. A projection 39 as shown in Fig. 2 is provided in each recess to serve as a shelf for the outer end portion of the arm of the spider type support I2 disposed in the recess. The projections 33 are integral with the-circular side wall 23 of the indentation 2| and extend longitudinally of the recesses. Each projection 39 is slightly less than half the length of the recess and is spaced a sufiicient distance from the upper wall 3I to permit the arm of the spider type supports I2' to pass over the upper surface of the projection 30. One at least of the projections 39 as shown in Figs. 2, 5, 6 and 7 is abruptly thickened on the outer end to form a latch 32 for the spider type support I2. The latch 32 may be seen in the recess 26 in Fig. 2.

The spider type support I2 may be made of sheet metal or any other material suitable for the purpose and provides a flexible support for the finger Wheel I I. It is illustrated as having three arms 21, 28 and 29 but may have a greater number if desired, the finger wheel II having a suitable number of recesses formed therein to accommodate the arms of the spider type support [2.

Located directly below and in parallel spaced relation with one of the arms of the spider type support I2, and in this case the arm 29, is a bar 33 equipped with an upwardly extending embossing 34. The bar 33 may be made of stiffer material than the spider type support I2 and is apertured on its inner end to accommodate the shaft I3. The bar 33 is slipped over the shaft I3 before the spider type support I2 is applied.

The spider type support I2 is centrally apertured to receive the shaft I3. The spider type support I2 and the bar 33 are formed and arranged to rotate with the shaft I3 and are clamped in position on the shaft I3 by means of the nut I4.

The finger wheel II may be latched to the spider type support I2 by placing the finger wheel II on the spider type support I2 and so that the outer ends of the arms 27, 28 and 29 pass upwardly within the respective recesses 24, 25 and 26 and above the projections 39 and into engagement with the upper Wall 3| and by rotating the finger wheel II counter-clockwise relative to the spider type support I2. This will bring the arms of the spider type support I2 directly over the projections 39 and the arm 29 past the latch 32 in the recess 26. The bar 33 will bear against the lower surface of the projection 30 in the recess 26. The spacing of the bar 33 from the arm 29 and the thickness of the latch 32 are such that the arm 29 is flexed slightly upward in passing over the latch 32. When the arm 29 passes to the right of and beyond the latch 32, the spring pressure developed in the arm 29 will cause it to snap down against the upper surface of the projection 39 in the recess 26 as shown in han Fig. 6. The bar 33 in engagement with the under surface of the projection 30 will prevent any normal bearing down force applied to the finger wheel l2 from causing release of the arm 29 from the latch 32. When the finger wheel II is mounted on the spider type support I2 and is rotated in a clockwise direction, the latch 32 forms a driving edge for the spider type support I2 and transmits the manual rotation of the Wheel II to the spider type support I2 so that the spring motor in the calling device is wound up to develop enough spring pressure therein to return the finger wheel I I to normal starting position, when the finger wheel II is released. In the return movement of the finger wheel I I and the spider type support I2, the contact controlling device I5 is operated in the well-known manner to operate the contacts I6 and I! so that the signal pulses are sent over the line system to control the operation of switches at the telephone central station in setting up the desired telephone call connection. When the finger wheel I I has been manually rotated to bring a desired finger hole 20 around to the stop 35, and is released from further manual rotation, the spring motor of the telephone calling device rotates the spider type support I2 back to normal position and the finger wheel is carried back by the spider type support to starting position by reason of the arm 29 bearing against the latch 32.

The finger wheel I! may be released from the spider type support l2 by placing a screw driver or other suitable tool between the bar 33 and the arm 29 and preferably over the embossing 34,

and then tilting the tool to flex the arm 29 above the latch 32. When the arm 29 is flexed above the latch 32 the finger wheel may be manually rotated in a clockwise direction and relative to the spider type support 12 to bring the arms 21, 28, and 29 clear of the projections 39 and into the portions of the recesses 24, 25 and 25 not occupied by the projections 39. The finger wheel II may then be lifted off the spider type support I2.

The integral window 22 in the finger wheel II serves as a cover for the telephone substation number card 36 which is placed against the under surface of the window 22 and held in position by some suitable means, the means for hold- "ing the number card 36 in position as shown in Fig. 1 may comprise a spring ring 3'! located in an annular groove 38 formed in the finger wheel The ring 31 is of slightly incomplete circular form as shown at 39 and is snapped into the groove 38 against the under surface of the outer edge portion of the card 36.

Fig. 3 shows a modification of the finger wheel construction above-described. In this case the finger wheel 40 is provided with a centrally apertured hub portion M, the internal diameter of which is somewhat less than the diameter of the station number card 36 and an overlying transparent cover disc 42. The card 36 and the disc 42 are placed in laminated form against an over- 43 in the hub portion 4I and are held in place by means of the spring ring 3'! which is snapped into the annular groove 38 in the same manner as in Fig. 1. The finger wheel in in all other respects is constructed like the finger wheel II' above described and is mounted on the flexible support I 2'.

Since the finger wheel in both constructions above described is supported on the flexible spider type support I2, considerable bearing down pres- =sure may be applied to the finger wheel by the operator of the device without causing fracture of the finger wheel. When an undue downward pressure is applied to the finger wheel, the flexible spider type support l2 will fiex downwardly in the region of the point of pressure and relieve the finger wheel of much of the strain it would otherwise be subjected to.

The finger wheel may be readily detached from the flexible spider type support l2 for replacement by another finger wheel or for changing the substation number card.

What is claimed is:

1. In a telephone calling dial device, in combination, a finger wheel recessed at a plurality of spaced points, projections extending into the recesses formed in said finger wheel, a flexible spider type support for said finger wheel having arms extending into said recesses, and overlying said projections, means underlying said spider type support and engaging the under surface of at least one of said projections and an enlarged end portion on at least one of said projections and in engagement with one of the arms of said spider type support.

2. In a telephone calling dial device, in combination, a finger wheel, spaced recesses formed in the under surface of said finger wheel, a projection extending into each of said recesses, a flexible spider type'support extending into said recesses and having arms engaging the upper surfaces of said projections, means extending in parallel spaced relation with at least one of the arms of said spider type support and engaging the under surface of at least one of said projections, and an abruptly enlarged end portion on at least one of said projections and bearing against one of the arms of said spider type support.

3. In a telephone calling dial device, in combination, a finger wheel having a circular indentation in its under surface, a plurality of spaced recesses formed in the circular wall of said indentation, projections integral with said wheel and extending into said recesses, a spider type supporting member of flexible material supporting said finger wheel, the arms of said spider type supporting member extending into said recesses and resting on said projections, an enlarged end portion on at least one of said projections and extending above the plane of the lower surface of said spider type supporting member and engaging one of the arms of said spider type supporting member, a bar extending in parallel spaced relation with at least one of the arms of said spider type supporting member and bearing against the under surface of at least one of said projections, and said bar and said enlarged end portion cooperating to latch said spider type supporting member to said finger wheel.

4. In a telephone calling dial device, in combination, a finger wheel having a central indentation formed in its lower face, an integral window in said finger wheel and closing the upper end of said indentation, spaced recesses formed in the side wall of said indentation, a projection extending into each of said recesses, a spider type supporting member of flexible material serving as a support for said finger wheel, arms on said spider type supporting member extending into said recesses and resting on said projections, a bar extending beneath said spider type supporting member and in spaced relation with at least one of the arms of saidspider type supporting member, said bar engaging the under surface of at least one of said projections, an embossing on said bar extending into the space between said bar and said spider type supporting member, an abruptly enlarged end portion on at least one of said projections and engaging one of the arms of said spider type supporting member, and said bar and said abruptly enlarged end portion cooperating to form a latch to hold said finger wheel secured to said spider type supporting member.

5. In a telephone calling dial device, comprising a rotatable shaft and means controlled by operation of said shaft to send signal pulses, in combination, a spider type support of flexible material mounted on said shaft and having arm members extending radially of said shaft, a finger wheel having a circular opening adapted to receive said spider type support, spaced recesses formed in said finger wheel and arranged to receive the outer ends of said arms of said spider type support, projections extending longitudinally into the recesses and arranged to form rests for the outer ends of said arms, a bar mounted on said shaft and extending below and in spaced relation with at least one of said arm members, and engaging the lower surface of at least one of said projections, an abrupt enlargement on the end of at least one of said projections and said bar and said enlargement serving in cooperation to latch said finger wheel to said spider type support.

GEORGE R. LUM. 

